Cap assembly for a drug delivery device, kit for assembling a cap, method for assembling a cap and drug delivery device comprising a cap assembly

ABSTRACT

A multi-part cap assembly for a drug delivery device is provided, the cap assembly comprising: a first cap component, and a second cap component, wherein the first cap component is assembled to the second cap component, wherein one of the first cap component and the second cap component is provided with a guide track and the other one of the first cap component and the second cap component is provided with a guide feature, wherein the guide track and the guide feature are arranged to cooperate to form an axial guiding interface between the first cap component and the second cap component, and wherein the axial guiding interface is configured such that relative rotational movement between the first cap component and the second cap component is restricted or prevented. Furthermore, a kit for assembling a cap and a method for assembling a cap are provided as well as a drug delivery device.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is the national stage entry of InternationalPatent Application No. PCT/EP2018/055544, filed on Mar. 7, 2018, andclaims priority to Application No. EP 17159522.6, filed on Mar. 7, 2017,the disclosures of which are incorporated herein by reference.

TECHNICAL FILED

The present disclosure relates to a cap or a cap assembly for a drugdelivery device, particularly a multi-part cap or multi-part capassembly, to a kit for assembling a cap, to a method for assembling acap and to a drug delivery device comprising the cap or cap assembly.

BACKGROUND

Drug delivery devices which do comprise a cap with a plurality of partsare, for example, known from WO 2015/028439 A1.

SUMMARY

The present disclosure provides solutions which facilitate the provisionof an improved cap assembly or cap and/or improve the production of thecap. It should be noted that, aside from the claimed subject matter, thepresent disclosure may also contain other advantageous configurationsand elements such that the present disclosure shall not be regarded asbeing limited to the claimed subject matter.

An aspect of the present disclosure is directed to a cap or a capassembly for a drug delivery device. Another aspect of the presentdisclosure is directed to a kit, which is expediently a kit forassembling a cap or cap assembly for a drug delivery device. Anotheraspect is directed to a method for assembling a cap or cap assembly fora drug delivery device. Yet another aspect is directed to a drugdelivery device comprising the cap or cap assembly.

Accordingly, features disclosed in connection with one of these aspectsare also considered as being disclosed for the other aspects. Likewise,features disclosed in conjunction with different embodiments may becombined with one another. The difference between the kit and the capassembly or cap is that, in the kit, the components or parts of the caphave not been assembled yet, whereas the cap assembly or cap refers to asituation where the components or parts have been assembled already.

In an embodiment, the cap or cap assembly comprises a first capcomponent and a second cap component. The first cap component may beadjusted to provide an inner or interior surface of the cap.Particularly, the first cap component may be formed in a sleeve-likeshape. The first cap component may be adjusted to receive a cartridge ofthe drug delivery device via a, preferably proximal, opening of the capassembly or the first cap component. The length of the cap assembly maybe greater than or equal to the length of a cartridge of the drugdelivery device. The second cap component may be designed to form anouter or exterior surface of the cap. Particularly, the second capcomponent may be formed in a sleeve-like shape. The first cap componentmay be made of or comprise a plastic material. The second cap componentmay be made of or comprise a metal or a metal based alloy. Consequently,the outer appearance of the cap can be governed by the second capcomponent, which suggests a durable and stable cap of high value,whereas the interior may be formed by the first cap component, which canbe designed to suit several functions easily, for example by way ofinjection moulding a plastic cap component, which enables the provisionof several functional features like snap features or other features inthe first cap component.

In an embodiment, the first cap component and the second cap componentcan be assembled to one another. The first cap component may, forexample, be received in and/or secured relative to the second capcomponent. When assembling the cap assembly, the first cap component maybe introduced into the second cap component, expediently via a proximalopening of the second cap component. When assembled, the first capcomponent and the second cap component may be secured to each other suchthat relative rotational and axial movement is prevented. The capassembly comprising the two cap components may thus act as a singlepart.

In an embodiment, the first cap component and/or the second capcomponent comprises one or more openings, e.g. two openings. Preferably,the respective cap component has at least an opening at the proximalend, i.e. the proximal opening. If there are two openings, there ispreferably one at the proximal end of the respective cap component andone at the distal end, i.e. the distal opening.

In the cap or cap assembly the first and second cap components areassembled to one another. The kit also comprises the first and secondcap components as detailed above, but not yet assembled to one another,and, in the method, the first and second cap component as detailed aboveare provided for assembling the cap.

In an embodiment, one of the first cap component and the second capcomponent is provided with or comprises a guide track, preferably anaxial guide track. The other one of the first cap component and thesecond cap component may be provided with or comprise a guide feature.The guide feature may be designed to cooperate with the guide track. Theguide track and the guide feature may be arranged to cooperate to form aguiding interface, preferably an axial guiding interface, between thefirst cap component and the second cap component. Consequently, when theguide feature and the guide track cooperate, i.e. when the guidinginterface is established, movement of the cap components relative toeach other, expediently in the axial and/or the angular or rotationaldirection, is governed by the guiding interface. The axial guidinginterface may be configured such that relative rotational movementbetween the first cap component and the second cap component isrestricted or prevented. The axial guiding interface is expedientlyconstructed such that relative axial movement, preferably only relativeaxial movement, between the first and second cap components is allowed.“Axial”, “radial”, “rotational”, and “angular” as used herein may beunderstood as being with respect to a main longitudinal axis of thecap/cap assembly or one or more components thereof such as the first orsecond cap component.

In an embodiment, the guiding interface is configured such that itrestricts relative rotational movement to angles of equal to or lessthan one of the following values: 10°, 5°, 4°, 3°, 2° or 1°, 0.75°,0.5°, 0.25°. Preferably, relative rotational movement is preventedentirely at least when the first and second cap components are fullyassembled. By restricting or preventing the relative rotational movementbetween the cap components, it can be assured that, expediently alreadyduring the assembling process, a defined relative rotational orientationof the two cap components is achieved, which may have significantadvantages. For example, features provided on one cap component do havea defined position relative to features on another cap component, whichwill simplify the assembling process and also increase the yield as capcomponents which have been assembled to each other in the wrong angularorientation might not be suitable for further use.

In an embodiment, the first cap component and/or the second capcomponent may be unitary. That is to say, the respective cap componentmay be formed as a single piece.

In an embodiment, the respective cap component may comprise a main bodywith the guide feature or the guide track being formed on the main bodyof the respective cap component.

In an embodiment, when assembling the multi-part cap assembly, the firstcap component and the second cap component may be arranged with respectto each other such that the guiding interface is established. For doingso, the first cap component may be introduced into the second capcomponent. The guiding interface may be established, preferably only,after a first portion of relative movement, particularly relative axialmovement, between the first cap component and the second cap componenthas been performed. In other words, before the guiding interface isestablished, there may be a situation where the guiding interface is notestablished, although the first cap component has already been receivedin the second cap component. After the guiding interface has beenestablished, the first cap component and the second cap component may bemoved relative to one another, particularly in the axial direction,towards an end position. This movement is expediently guided by theguiding interface, preferably from the onset of the guiding interfaceuntil the end position has been reached. In the end position, the firstcap component and the second cap component may be secured to oneanother, expediently against relative axial and/or rotational movement.

In an embodiment, the cap, the first cap component and/or the second capcomponent do define a longitudinal axis, particularly a mainlongitudinal axis. The axes of the two cap components may coincide or beparallel.

In an embodiment, the guide track may extend in the axial direction. Theguide track may be a straight track. The guide track may extend alongthe longitudinal axis, preferably parallel with respect to the axis. Theguide track may coincide with the longitudinal axis when projected ontoa plane comprising the axis. In other words, when seen in projectiononto a plane which comprises the main longitudinal axis but does notcomprise the guide track the guide track and the longitudinal axis maycoincide.

In an embodiment, the first cap component and the second cap componentare configured such that the relative angular orientations of the firstcap component and the second cap component, in which the first capcomponent can be assembled to, e.g. arranged in the end position withrespect to, the second cap component, are limited. This holds,preferably, even when disregarding the guiding interface mentionedabove. Accordingly, aside from the guiding interface, the cap componentsmay be designed such that they can be assembled to each other only in alimited number of relative angular orientations.

In an embodiment, the inner cross section of the second cap componentand the outer cross section of the first cap component may be adjustedto one another at least in an adjusted region of the respectivecomponent. The adjustment may be performed by shaping the outer surfaceof the first cap component and the inner surface appropriately in theadjusted region of the respective cap component. When the cap componentsare misaligned, relative axial movement is not possible as the crosssectional shape does not permit this movement. When the cap componentsare aligned correctly, however, the adjusted sections of the crosssection cooperate, e.g. they form a rotationally constrained interfaceor an interface of limited relative rotatability between the twocomponents, and relative axial movement is possible.

Therefore, the first cap component and the second cap component can bepre-aligned, even if the guiding interface is not yet established.Consequently, the guide feature and the guide track may be pre-alignedsuch that they can be brought into mechanical cooperation for formingthe guiding interface more easily and more reliably during the assemblyof the cap assembly.

In an embodiment, the cap components are expediently designed such thata splined interface or pre-alignment interface is formed between the capcomponents while the two components are being assembled to one anotherand before the guiding interface is established by cooperation of theguide feature and the guide track.

In an embodiment, the relative angular orientations in which the firstand second cap components can be assembled to one another are limited toa range of orientation angles, preferably a single and continuous rangeof orientation angles. Consequently, even when the axial guidinginterface is not or not yet established, the cap components may bealigned in the range of orientation angles. The guiding interface isexpediently configured to restrict the relative rotational movementwhich is permitted between the first cap component and the second capcomponent to a restricted range of angles. The restricted range ofangles is expediently smaller, e.g. has a smaller extension, than therange of orientation angles. The restricted range of angles may be asubset of the range of orientation angles. The range of orientationangles is expediently such that the intended position in which the firstand second cap components should be assembled is at 0° with deviationspossible in both rotational directions up to to −α1 and +α2,respectively. α1 and α2 may be different or equal. By means of thepre-alignment, α1 and/or α2 may be already restricted to values equal toor less than one of the following values: 30°, 25°, 20°, 15°, 10°, 5°.The guiding interface may restrict the relative rotatability even moreor prevent relative rotatability entirely. Consequently, by providingthe guide track and the guide feature, a very defined relativerotational position may be assumed by the first and second capcomponents during the assembly and/or in the end position once theassembling process has been completed.

In an embodiment, the guiding interface is established in the endposition. The guide track may comprise an axial end stop whichcooperates with the guide feature to indicate when the end position hasbeen reached.

In an embodiment, the guide track is a slot or a groove.

In an embodiment, the guide feature has one or more curved surfaces. Therespective curved surface may be designed to interact with the guidetrack. A reliable guiding interface may be realized in this way. Therespective surface may extend in the radial direction.

In an embodiment, the cap assembly comprises a third cap component. Thethird cap component may comprise or be provided with a third capcomponent fixing feature, e.g. a snap feature. The third cap componentmay be a clip element for the cap assembly. The clip element may bedesigned such that the cap can be clipped to a pocket or the like.

In an embodiment, the first cap component is provided with or comprisesa first cap component fixing feature, e.g. a snap feature. The third capcomponent may be fixed to the first cap component by means of the firstcap component fixing feature. The first cap component fixing feature isexpediently designed and arranged to cooperate with the third capcomponent fixing feature provided on the third cap component in order tofix the third cap component to the first cap component.

In an embodiment, the second cap component is provided with or comprisesa fixing guide track, in particular an axial or axially extending fixingguide track. The fixing guide track may be arranged to guide movement ofthe third cap component and/or the third cap component fixing means toor towards the first cap component fixing means. In other words, thesecond cap component may interact with the third cap component in orderto guide a fixing feature of the third cap component to the first capcomponent fixing feature. As the guiding interface ensures a definedrelative angular position between the second cap component and the firstcap component it is also ensured that the third cap component fixingfeature is reliably guided to the first cap component fixing feature andmay cooperate with the first cap component fixing feature.

In an embodiment, the axial fixing guide track and the axial guide trackextend in, are arranged in and/or are restricted to a common plane whenthe axial guiding interface is established. This plane may be a planewhich also comprises the main longitudinal axis of the cap assembly orof components thereof.

In an embodiment, the third cap component is used to secure the firstcap component and the second cap component with respect to one another,in particular with respect to relative axial movement. Consequently,when the first cap component fixing feature and the third cap componentfixing feature cooperate, relative axial movement between the first capcomponent and the second cap component is prevented. Relative rotationalmovement may also be prevented by the third cap component and/or by theguiding interface, which may be still operative in the end position.

In an embodiment, the third cap component fixing feature and the firstcap component fixing feature are arranged to cooperate, particularlyonly, when they are arranged in a fixing range of relative angularpositions or orientations with respect to one another. Thus, even ifthey were at the correct relative axial position, i.e. correspondingaxial locations, the fixing features could not cooperate if theirrelative angular position or orientation is arranged outside of thefixing range. Similar as above, 0° is the ideal relative angularposition or orientation in which the fixing features should be arrangedto allow cooperation. The tolerance which has to be met for stillallowing proper cooperation of the fixing features may be as low as 1°or even less from the ideal position. Thus, the fixing range is verysmall. The fixing range may fully cover the relative angular positionsor orientations in the restricted range of angles, when the guidinginterface is established. The fixing range may not fully cover therelative angular positions orientations in the range of orientationangles. That is to say, the range of relative angular orientations whichis possible when disregarding the guiding interface may compriseorientation angles where the fixing features of the first and third capcomponents could not cooperate. The guiding interface, however,restricts the range of possible relative angular positions ororientations to the restricted range of angles, where it is ensured thatthe fixing features can cooperate. In other words, a fixing range ofangles may fully cover the restricted range of angles but not the rangeof orientation angles.

In an embodiment, the second cap component forms an outer surface of thecap assembly. The second cap component may be made of metal or of ametal alloy.

In an embodiment, the second cap component is a deep drawn component.Deep drawing facilitates the manufacturing of a metal or metal alloysecond cap component. Deep drawing is a production method for metalcomponents which is very cost effective, is suitable for high volumes,and/or ensures a high yield.

In an embodiment, the guide track is provided on the first cap componentand the guide feature is provided on the second cap component or viceversa. Expediently, the guide feature is arranged on an inner surface ofthe second cap component and the guide track is arranged on an outersurface of the first cap component.

In an embodiment, the guide feature is formed by a protrusion. Theprotrusion may extend in the radial direction. The protrusion may beprovided on an inner surface of the second cap component. The protrusionmay be realised by deep drawing. The protrusion may protrude from a mainbody of the respective cap component. The protrusion may have ahemispherical shape.

In an embodiment, the second cap component, particularly an outersurface thereof, comprises a depression. The depression may have ahemispherical shape. The depression may be formed by a pressingoperation that occurs as part of a multi-stage deep-drawing process. Theprotrusion may be defined by the depression. This facilitatesmanufacturing the protrusion in a deep drawing process as protrusion anddepression can be formed simultaneously.

In an embodiment, the guide feature, particularly the protrusion, isdefined by a depression. The guide feature may be arranged on theopposite surface of the same cap component which comprises thedepression. The depression may be the same depression as discussedfurther above.

In an embodiment, a section of the third cap component, particularly aradially extending section of the third cap component, which protrudesradially from the remainder of the third cap component, may be arrangedin the depression. Consequently, the depression may provide for abearing surface of a clip element of the cap assembly.

In an embodiment, the third cap component or clip element is amulti-part component. The third cap component may comprise a first orinner part, preferably a plastic part, which is connected with a secondor outer part, e.g. an outer shell, preferably of metal or a metalalloy.

In an embodiment, the guide track comprises a lead-in region, preferablyat the start of the guide track. Via a transition region of the guidetrack, the lead-in region may pass into a guiding region. In the lead-inregion, the relative orientation angles, in which the guide feature cancooperate with the guide track may be wider than in the guiding region.In other words, the lead-in region may be arranged to accept the guidefeature and guide the guide feature to a guiding region of the guidetrack, in which the guide feature is guided more tightly than in thelead-in region. This ensures a tight guiding when the guiding interfaceis established, which is expediently the case when the guide feature andthe guiding region cooperate. Consequently, even if the first and secondcap components are misorientated or misaligned with respect to oneanother in the angular direction such that the guide feature could,without the lead-in region, not cooperate with the guide track, thelead-in region can capture the guide feature during relative axialmovement of the cap components during the assembling process and orientthe first and second cap components appropriately in the angulardirection such that the guide feature and the guiding region of theguide track can cooperate.

In an embodiment, the drug delivery device, which comprises the capassembly, comprises a cartridge containing a drug, preferably aplurality of doses of the drug, which is preferably a fluid drug. Thedrug delivery device is expediently configured such that the cartridgeis replaceable. In other words, the drug delivery device is preferablyreusable. The device may be a pen-type device.

In a preferred embodiment, a multi-part cap assembly for a drug deliverydevice comprises a first cap component and a second cap component,wherein the first cap component is assembled to, in particular receivedin and/or secured relative to, the second cap component, wherein one ofthe first cap component and the second cap component is provided with aguide track and the other one of the first cap component and the secondcap component is provided with a guide feature, wherein the guide trackand the guide feature are arranged to cooperate to form an axial guidinginterface between the first cap component and the second cap component,and wherein the axial guiding interface is configured such that relativerotational movement between the first cap component and the second capcomponent is restricted or prevented.

In a further preferred embodiment, a kit for assembling a multi-part capfor a drug delivery device comprises a first cap component and a secondcap component which can be assembled for the cap assembly, wherein thefirst cap component can be received in and secured relative to thesecond cap component, and wherein one of the first cap component and thesecond cap component is provided with a guide track and the other one ofthe first cap component and the second cap component is provided with aguide feature, wherein the guide track and the guide feature arearranged to cooperate to form an axial guiding interface between thefirst cap component and the second cap component, and wherein the axialguiding interface is configured such that relative rotational movementbetween the first cap component and the second cap component isrestricted or prevented.

In a further preferred embodiment, a method for assembling a multi-partcap for a drug delivery device comprises the steps of:

providing a first cap component,

providing a second cap component, wherein one of the first cap componentand the second cap component is provided with a guide track and theother one of the first cap component and the second cap component isprovided with a guide feature, wherein the guide track and the guidefeature are arranged to cooperate to form an axial guiding interfacebetween the first cap component and the second cap component, andwherein the axial guiding interface is configured such that relativerotational movement between the first cap component and the second capcomponent is restricted or prevented,

introducing the first cap component into the second cap component suchthat the axial guiding interface is established, moving the first capcomponent and the second cap component relative to one another in theaxial direction towards an end position, this movement being guided bythe axial guiding interface, and

securing the first cap component and the second cap component to oneanother in the end position.

The preferred embodiments discussed above do have particular advantageswhich become apparent from the description further above and thefollowing description.

Features which are described herein above and below in conjunction withdifferent aspects or embodiments, may also apply for other aspects andembodiments. Further features and advantageous embodiments of thepresent disclosure will become apparent from the following descriptionof the exemplary embodiments in conjunction with the figures, in which:

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a drug delivery device with a cap attached in accordancewith an embodiment;

FIG. 2 shows the drug delivery device of FIG. 1 with the cap removed anda dose of 79 units dialed;

FIG. 3 shows in an exploded view the components of the drug deliverydevice of FIG. 1;

FIG. 4 shows the outer body of the drug delivery device of FIG. 1;

FIG. 5a shows the inner body of the drug delivery device of FIG. 1;

FIG. 5b shows a detail of the inner body of FIG. 5 a;

FIG. 6 shows the cartridge holder of the drug delivery device of FIG. 1;

FIG. 7a shows a first display member component of the drug deliverydevice of FIG. 1;

FIG. 7b shows a detail of the first display member of FIG. 7 a;

FIG. 8 shows a second display member component of the drug deliverydevice of FIG. 1;

FIG. 9 shows a first driver component of the drug delivery device ofFIG. 1;

FIG. 10 shows a second driver component of the drug delivery device ofFIG. 1;

FIG. 11 shows a third driver component of the drug delivery device ofFIG. 1;

FIG. 12 shows the last dose nut of the drug delivery device of FIG. 1;

FIG. 13 shows a clutch component of the drug delivery device of FIG. 1;

FIG. 14 shows a first clicker component of the drug delivery device ofFIG. 1;

FIG. 15 shows a second clicker component of the drug delivery device ofFIG. 1;

FIG. 16 shows the button of the drug delivery device of FIG. 1;

FIG. 17 shows a cut-away view of the proximal part of the drug deliverydevice of FIG. 1 in a zero unit position with the button released;

FIG. 18 shows a cut-away view of the proximal part of the drug deliverydevice of FIG. 1 in a position with some units dialed; and

FIG. 19 shows a cut-away view of the proximal part of the drug deliverydevice of FIG. 1 in a zero unit position with the button pressed.

FIG. 20 shows an exploded view of a cap assembly;

FIG. 21 shows a sectional view of a proximal region of an outer capelement;

FIG. 22 shows a three-dimensional cut out view of the outer cap element;

FIG. 23 shows a sectional view of the proximal section of the cap duringattachment;

FIG. 24 shows a sectional view of the proximal section of the cap afterattachment;

FIG. 25 shows a sectional view of the proximal section of an alternativeembodiment of the cap after attachment;

FIG. 26 shows a perspective view of a first component of a clip element;

FIG. 27 shows a perspective view of an outer component;

FIG. 28 shows a perspective view of an inner component;

FIG. 29 shows a schematic cross-sectional view of parts of a capassembly;

FIG. 30 shows a portion of the cap assembly in a longitudinal section;

FIG. 31 shows a perspective view of a first component of a clip element;

FIG. 32 shows a perspective view of a cap assembly;

FIG. 33 shows a sectional view of the cap assembly of FIG. 32;

FIG. 34 shows a distal portion of a clip element;

FIG. 35 shows a sectional view of a component of a clip element;

FIG. 36 shows a sectional view of a clip element;

FIG. 37 shows a sectional view of a clip element;

FIG. 38 shows another sectional view of the clip element of FIG. 37;

FIG. 39 shows a portion of the clip element of FIG. 38.

FIG. 40 shows parts of an embodiment of a cap assembly in an unassembledstate.

FIG. 41 shows the cap assembly with the parts shown in FIG. 40 in anassembled state.

FIG. 42 shows a state during the assembling of the cap assembly of FIG.41 on the basis of a partial sectional view in FIG. 42A and aperspective view in FIG. 42B.

FIG. 43 shows a side view of the cap assembly.

Like elements, elements of the same kind and identically acting elementsmay be provided with the same reference numerals in the figures.Additionally, the figures may be not true to scale. Rather, certainfeatures may be depicted in an exaggerated fashion for betterillustration of important principles.

DETAILED DESCRIPTION

FIGS. 1 and 2 show a drug delivery device 1 in the form of an injectionpen. Consequently, references herein using the wording “an injectionpen” or similar wordings should also be understood as relating to a drugdelivery device, preferably a pen-type drug delivery device. The device1 has a distal end (lower end in FIG. 1) and a proximal end (upper endin FIG. 1). The components of the drug delivery device 1 are shown inFIG. 3 in more detail. The drug delivery device 1 comprises an outerhousing part 10, an inner body 20, a piston rod 30, a driver 40, a nut50, a display member 60, a button 70, a cartridge holder 80 forreceiving a cartridge 81, a clutch 90, a clicker 100, a spring 110, acap 120 and a window insert 230. A needle arrangement (not shown)comprising a needle hub and a needle cover may be provided as additionalcomponents, which can be exchanged. The piston rod 30 comprises abearing 31. The driver 40 comprises a distal driver part 41, a proximaldriver part 42 and a coupler 43. The display member 60 comprises anumber sleeve 61 and a dial sleeve 62. The clicker 100 comprises adistal clicker part 101, a proximal clicker part 102 and a spring 103.

The outer housing part 10, which is shown in FIG. 4, is a generallytubular element having a distal part 11 for attaching the inner body 20and a proximal part, which is provided with a rotational hard stop 12 onits inner surface (not shown) which contact mating faces of the displaymember 60 when the maximum units (in this example 80 U) stop is engaged.The end face also serves as the end of dose dispense stop for the button70, and the bore in the end face centers the display member 60 duringboth dialing and dispense. An aperture 13 is provided for receivingwindow insert 230. The outer body 10 provides the user with a surface togrip and react against during dispense.

The inner body 20 is a generally tubular element having differentdiameter regions. As can be seen in FIGS. 17 to 19, the inner body 20 isreceived in the outer body 10 and permanently fixed therein to preventany relative movement of the inner body 20 with respect to the outerbody 10. The inner body has the functions to house the drive mechanismwithin, guiding the clickers and the last dose nut 50 via internalsplines, to provide an internal thread through which the piston rod 30(lead screw) is driven, to support and guide the number sleeve 61 andthe dial sleeve 62 on an external thread form, to secure the cartridgeholder 80 and to secure the outer body 10 and the window insert 230.

The outermost diameter of the inner body 20 also forms part of thevisual design and remains visible when the cap 120 is secured to thecartridge holder 80 as a ring separating the cap 120 from the outer body10. This visible ring also has depressions which align with the cap snapfeatures on the cartridge holder 80 to indicate that the cartridgeholder has been correctly fitted.

An external thread 21 is provided on the outer surface of the inner body20. Further, splines 22 (FIG. 5b ) are provided on the inner surface ofthe inner body 20. These internal splines 22 guide the clicker 100axially during both dialing and dispense and also prevent the last dosenut 50 from rotating. Some of the splines may be wider to ensure correctrotational assembly of the internal components, and these wider splinesmay have a stepped entry and angled surface to encourage the last dosenut 50 to rotate up against the stop face on the distal drive sleeve 41during assembly. At the open end shown in FIG. 5b there are additionalshort splines which together with the alternating long splines 22 areused to rotationally lock the button 70 (dose dial grip) at the end ofdispense and serve to increase the strength of the 0 U dial stop whenthe button 70 is depressed. This is achieved by engagement with malespline features on the clutch component 90.

Bayonet features 23 guide the cartridge holder 80 into the mechanismduring cartridge replacement, compressing the cartridge bias spring 110,and then back off the cartridge holder 80 a small distance in order toreduce axial play in the mechanism. Snap features inside the inner body20 lock the cartridge holder 80 rotationally when it has been correctlyfitted. The profile of these snaps aims to prevent the user frompartially fitting the cartridge holder 80, the cartridge bias spring 110ejecting the cartridge holder 80 if the snaps have not at least startedto engage. A window retention nose 24 retains the window insert 230 whenthe outer body 10 and window insert 230 assembly is axially insertedonto the inner body 20. Two diametrically opposite stop faces 25 definethe rotational end position for the number sleeve 61. This end positionis the end of dose detent position for the minimum dose (0 U).

The piston rod 30 is an elongate element having two external threads 32,33 with opposite hand which overlap each other. One of these threads 32engages the inner thread of the inner body 20. A disk-like bearing 31 isprovided at the distal end of the piston rod 30. The bearing 31 may be aseparate component as shown in FIG. 3 or may be attached to the pistonrod 30 as a one-piece component via a predetermined breaking point.

The piston rod 30 transfers the dispense load from the driver 40 to thebearing 31, creating a mechanical advantage greater than 1:1 byconverting the torque generated on the piston rod 30 by the driver 40thread interface into additional axial load as the piston rod passesthrough the thread in the inner body 20. The piston rod 30 is reset bypressing on the bearing 31 and this in turn rotates the piston rod backinto the inner body 20. This disengages and then rotates the distaldrive sleeve 41, resetting the last dose nut 50 back to its startingposition on the distal drive sleeve 41.

The driver 40 is a generally tubular element having in the embodimentshown in the Figures three components which are depicted in FIGS. 9 to11 in more detail.

The distal drive sleeve 41 engages with the piston rod thread 33 todrive the piston rod 30 through the inner body 20 during dose delivery.The distal drive sleeve 41 is also permanently connected to the coupler43 which in turn is releasably engaged through reset clutch features tothe proximal drive sleeve 42. The two halves of the drive sleeve arerotationally and axially connected during dialing and dispense, but arede-coupled rotationally during device reset so that they can rotaterelative to each other.

The external thread 44 engages with the last dose nut 50. The threadform has three stages, a shallow first stage (left hand side in FIG. 9)over which the nut 50 travels to count the majority of the units dialed,a fast stage over which the last dose nut moves rapidly axially prior toengaging the stop faces, and a final shallow section which ensures thatwhen the stop faces have engaged, the axial restraint on the nut 50extends over a reasonable length of thread form. Four equi-spaced stopfaces 45 engage with mating stop faces 51 on the last dose nut 50 tolimit the number of units that can be dialed. Splines 46 are provided atthe proximal end of distal drive sleeve 41 to transfer torque from or tothe coupler 43, which may be snapped on the distal drive sleeve 41.

The proximal drive sleeve 42 shown in FIG. 10 supports the clickercomponents 100 and the clutch 90 and transfers rotational movement fromthe dose button 90 to the coupler 42 and distal drive sleeve 41.

Teeth features 47 located at the distal end of proximal drive sleeve 42engage with the reset clutch features on the coupler 43 to connect bothhalves of the drive sleeve during dialing and dispense. During resetthese teeth 47 disengage.

Several splines are provided on the outer surface of proximal drivesleeve 42 engaging with the distal and/or proximal clicker part 101,102,preventing relative rotation during dialing and dispense. Furthersplines, which are located in the middle region of proximal drive sleeve42, engage with the clutch 90 component. They may be arranged to berotationally non-symmetric so that the various clicker components cannotbe assembled accidentally upside down.

The proximal portion of proximal drive sleeve 42 has four arms orfingers 48. A hook-like bearing surface 49 exists on the underside (asseen in FIG. 10) of flange segments on the end of the flexible fingers48. The flexible fingers 48 are separated with gaps or slots that makespace for the button 70 to snap to the clutch 90 and also enable thesefingers to flex inwards during assembly of the proximal drive sleeve 42to the dial sleeve 62. After assembly the hooks 49 retain the proximaldrive sleeve 42 relative to the dial sleeve 62 under the reaction forcefrom the spring 103. During dispense the button 70 depresses the spring103 via the clutch 90 and the clicker components and this spring 103 isreacted through the coupler 43 to the proximal drive sleeve 42 whichthen through these bearing surfaces applies axial load to the dialsleeve 62. This axial load drives the dial sleeve 62 and hence numbersleeve 61 along the helical thread of the inner body 20, back into thebody of the device, until the 0 U stop faces on the number sleeve 61contact the inner body 20.

The coupler 43 shown in FIG. 11 rotationally couples the two halves ofthe drive sleeve together during dialing and dispense, whilst allowingthem to de-couple during reset. The coupler 43 has to also transfer thelast dose protection stop load from the proximal drive sleeve 42 to thedistal drive sleeve 41. Two sets of teeth are provided in the coupler 43for engaging teeth 46 and teeth 47, respectively. The coupler 43 issnapped onto distal drive sleeve 41 allowing limited relative axialmovement with respect to the proximal drive sleeve 42.

The nut 50 is provided between the inner body 20 and the distal drivesleeve 41 of driver 40. Stop faces 51 are located on the proximal faceof last dose nut 50 to limit the number of units that can be dialed ifthe stop faces 51 contact stops 45 of distal drive sleeve 41. Thefunction of the last dose nut 50 is to prevent the user from dialingbeyond a finite amount. This limit is based on the dispensable volume ofthe cartridge 81 and when reached, the user must replace the cartridge81 and reset the device.

External ribs 52 of the nut 50 engage splines 22 of inner body 20. Aninternal thread 53 of the nut engages the external thread 44 of distaldrive sleeve 41. As an alternative, splines and ribs could be providedon the interface between the nut 50 and the driver 40 and threads couldbe provided on the interface between the nut 50 and the inner body 20.As a further alternative, the nut 50 may be designed as e.g. a half nut.

The display member 60 is a generally tubular element which is composedof number sleeve 61 and dial sleeve 62 which are snapped together duringassembly to axially and rotationally constrain these two components,which thus act as a single part.

The main functions of the number sleeve 61 depicted in FIG. 8 are toprovide a surface onto which dose numbers can be printed to display thedialed dose, to guide the helical path of the internal mechanism duringdialing to follow the helical thread form on the piston rod 30 whenthreaded to the inner body 20 and to attach to the dial sleeve 62.

The number sleeve 61 is designed to be fully enclosed in the outer body10 during dialing and dispense and therefore only the dialed dose isvisible to the user through the window aperture. The number sleeve has a0 U (minimum dose) stop face 63 to limit its travel when dialed in butthe 80 U (maximum dose) stop faces that limit the dialed out conditionare located on the dial sleeve 62. At the end of each dispense stroke,this stop face 63 engages with mating surface 25 on the inner body 20 tolimit the rotational position of the number sleeve 61.

A helical drive face 64 forms a thread that guides the number sleeve 61during dialing and dispense to follow the helical path 21 on the innerbody.

The dial sleeve 62 is assembled to the number sleeve 61 such that onceassembled, no relative movement is allowed. The parts are made asseparate components to enable both molding and assembly. Also, whereasthe number sleeve 61 is preferably white to give contrast for the e.g.black dose numbers, the dial sleeve 62 color can be chosen to suit theaesthetics or perhaps to distinguish the drug type.

At the proximal end, the dial sleeve 62 has internal clutch features 65that engage with the clutch component 90 during dialing and disengagefrom the clutch during dispense. These clutch features 65 rotationallylock the dial sleeve 62 to the clutch 90 during dialing and when the 0 Uand 80 U stops are engaged. When the button 70 is depressed these clutchfeatures disengage to allow the clutch 90 and drive mechanism to moveaxially whilst the dial sleeve 62 and number sleeve 61 spin back to the0 U start position.

The dial sleeve 62 rotates out during dialing through its engagementwith the clutch 90 and number sleeve 61, and rotates back in duringdispense under the axial force applied by the proximal drive sleeve 42to a flange-like bearing face 66 on the end of the dial sleeve. Thisbearing face 66 engages with the flexible arms 48 of the proximal drivesleeve 42 during dispense. Two diametrically opposite faces 67 engagewith the outer body 10 when the maximum dose (e.g. 80 U) has beendialed, forming the maximum dose stop faces.

A ratchet arm 68 engages with ratchet features on the button 70 (dosedial grip) to provide audible feedback during dispense, giving one clickper unit delivered. Further, this prevents the user from gripping androtating the number sleeve 61 outwards from a partially dialed outposition whilst holding the button 70 pressed in. This would back windthe piston rod 30 which would result in an under dose on the subsequentdialed dose. It may further strengthen the 0 U stop.

The button 70 which is shown in FIG. 16 serves as a dose dial grip andis retained by the clutch 90 to transfer the actions of the user to theclutch. It also carries ratchet teeth 71 that engage the ratchet arm 68on the dial sleeve 62, which serves as the dispensing clicker givingaudible feedback (ratchet clicks), and an end face 72 which serves asthe dose completion stop face with the outer body 10. This end face 72thus serves to define the end position during dispense when it contactsthe outer body 10 to provide a very positive stop improving doseaccuracy.

A central sleeve-like portion of button 70 is provided with four arms 73having hook-like snap features 74 at their respective distal ends. Thearms 73 form splined surfaces engaging with the clutch 90 to transfertorque from the button 70 through the clutch to the dial sleeve 62 andproximal drive sleeve 42. The snap features 74 engage apertures in theclutch 90 and are designed with angled undercut faces to maintainengagement when an axial load is applied to pull the button 70 out ofthe pen body 10. The space between arms 73 defines pockets givingclearance for the flexible arms 48 of proximal drive sleeve 42 to slidefreely relative to the button 70 and clutch 90 when the button 70 isdepressed and released during dose dispense.

The cartridge holder 80 attaches to the inner body 20 with a bayonetconnection 82 and houses the glass ampoule or cartridge 81 containingthe medication to be dispensed. The cartridge holder 80 includes anaperture 83 in the rear face (as seen in FIG. 6) which if gripped by theuser prevents the ampoule from falling out when the cartridge holder isremoved from the inner body 20. The front face is printed with a dosenumber scale. The threaded distal end 84 is used to attach disposablepen needles.

The term “drug” or “medication”, as used herein, preferably means apharmaceutical formulation containing at least one pharmaceuticallyactive compound, wherein in one embodiment the pharmaceutically activecompound has a molecular weight up to 1500 Da and/or is a peptide, aproteine, a polysaccharide, a vaccine, a DNA, a RNA, an enzyme, anantibody or a fragment thereof, a hormone or an oligonucleotide, or amixture of the above-mentioned pharmaceutically active compound,

wherein in a further embodiment the pharmaceutically active compound isuseful for the treatment and/or prophylaxis of diabetes mellitus orcomplications associated with diabetes mellitus such as diabeticretinopathy, thromboembolism disorders such as deep vein or pulmonarythromboembolism, acute coronary syndrome (ACS), angina, myocardialinfarction, cancer, macular degeneration, inflammation, hay fever,atherosclerosis and/or rheumatoid arthritis,

wherein in a further embodiment the pharmaceutically active compoundcomprises at least one peptide for the treatment and/or prophylaxis ofdiabetes mellitus or complications associated with diabetes mellitussuch as diabetic retinopathy,

wherein in a further embodiment the pharmaceutically active compoundcomprises at least one human insulin or a human insulin analogue orderivative, glucagon-like peptide (GLP-1) or an analogue or derivativethereof, or exendin-3 or exendin-4 or an analogue or derivative ofexendin-3 or exendin-4.

Insulin analogues are for example Gly(A21), Arg(B31), Arg(B32) humaninsulin; Lys(B3), Glu(B29) human insulin; Lys(B28), Pro(B29) humaninsulin; Asp(B28) human insulin; human insulin, wherein proline inposition B28 is replaced by Asp, Lys, Leu, Val or Ala and wherein inposition B29 Lys may be replaced by Pro; Ala(B26) human insulin;Des(B28-B30) human insulin; Des(B27) human insulin and Des(B30) humaninsulin.

Insulin derivates are for example B29-N-myristoyl-des(B30) humaninsulin; B29-N-palmitoyl-des(B30) human insulin; B29-N-myristoyl humaninsulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29human insulin; B28-N-palmitoyl-LysB28ProB29 human insulin;B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N-palmitoyl-ThrB29LysB30human insulin; B29-N-(N-palmitoyl-Y-glutamyl)-des(B30) human insulin;B29-N-(N-lithocholyl-Y-glutamyl)-des(B30) human insulin;B29-N-(ω-carboxyheptadecanoyl)-des(B30) human insulin andB29-N-(ω-carboxyheptadecanoyl) human insulin.

Exendin-4 for example means Exendin-4(1-39), a peptide of the sequenceH-His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2.

Exendin-4 derivatives are for example selected from the following listof compounds:

H-(Lys)4-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

H-(Lys)5-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

des Pro36 Exendin-4(1-39),

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [TrpO2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39); or

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39),

wherein the group -Lys6-NH2 may be bound to the C-terminus of theExendin-4 derivative;

or an Exendin-4 derivative of the sequence

des Pro36 Exendin-4(1-39)-Lys6-NH2 (AVE0010),

H-(Lys)6-des Pro36 [Asp28] Exendin-4(1-39)-Lys6-NH2,

des Asp28 Pro36, Pro37, Pro38Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Trp(O2)25] Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Met(O)14, Asp28] Exendin-4(1-39)-Lys6-NH2,

des Met(O)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1-39)-NH2,

H-(Lys)6-desPro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Lys6-des Pro36 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25]Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(S1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2;

or a pharmaceutically acceptable salt or solvate of any one of theafore-mentioned Exendin-4 derivative.

Hormones are for example hypophysis hormones or hypothalamus hormones orregulatory active peptides and their antagonists as listed in RoteListe, ed. 2008, Chapter 50, such as Gonadotropine (Follitropin,Lutropin, Choriongonadotropin, Menotropin), Somatropine (Somatropin),Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin,Buserelin, Nafarelin, Goserelin.

A polysaccharide is for example a glucosaminoglycane, a hyaluronic acid,a heparin, a low molecular weight heparin or an ultra low molecularweight heparin or a derivative thereof, or a sulphated, e.g. apoly-sulphated form of the above-mentioned polysaccharides, and/or apharmaceutically acceptable salt thereof. An example of apharmaceutically acceptable salt of a poly-sulphated low molecularweight heparin is enoxaparin sodium.

Antibodies are globular plasma proteins (˜150 kDa) that are also knownas immunoglobulins which share a basic structure. As they have sugarchains added to amino acid residues, they are glycoproteins. The basicfunctional unit of each antibody is an immunoglobulin (Ig) monomer(containing only one Ig unit); secreted antibodies can also be dimericwith two Ig units as with IgA, tetrameric with four Ig units liketeleost fish IgM, or pentameric with five Ig units, like mammalian IgM.

The Ig monomer is a “Y”-shaped molecule that consists of fourpolypeptide chains; two identical heavy chains and two identical lightchains connected by disulfide bonds between cysteine residues. Eachheavy chain is about 440 amino acids long; each light chain is about 220amino acids long. Heavy and light chains each contain intrachaindisulfide bonds which stabilize their folding. Each chain is composed ofstructural domains called Ig domains. These domains contain about 70-110amino acids and are classified into different categories (for example,variable or V, and constant or C) according to their size and function.They have a characteristic immunoglobulin fold in which two β sheetscreate a “sandwich” shape, held together by interactions betweenconserved cysteines and other charged amino acids.

There are five types of mammalian Ig heavy chain denoted by α, δ, ε, γ,and μ. The type of heavy chain present defines the isotype of antibody;these chains are found in IgA, IgD, IgE, IgG, and IgM antibodies,respectively.

Distinct heavy chains differ in size and composition; α and γ containapproximately 450 amino acids and δ approximately 500 amino acids, whileμ and ε have approximately 550 amino acids. Each heavy chain has tworegions, the constant region (C_(H)) and the variable region (V_(H)). Inone species, the constant region is essentially identical in allantibodies of the same isotype, but differs in antibodies of differentisotypes. Heavy chains γ, α and δ have a constant region composed ofthree tandem Ig domains, and a hinge region for added flexibility; heavychains μ and ε have a constant region composed of four immunoglobulindomains. The variable region of the heavy chain differs in antibodiesproduced by different B cells, but is the same for all antibodiesproduced by a single B cell or B cell clone. The variable region of eachheavy chain is approximately 110 amino acids long and is composed of asingle Ig domain.

In mammals, there are two types of immunoglobulin light chain denoted byλ and κ. A light chain has two successive domains: one constant domain(CL) and one variable domain (VL). The approximate length of a lightchain is 211 to 217 amino acids. Each antibody contains two light chainsthat are always identical; only one type of light chain, κ or λ, ispresent per antibody in mammals.

Although the general structure of all antibodies is very similar, theunique property of a given antibody is determined by the variable (V)regions, as detailed above. More specifically, variable loops, threeeach the light (VL) and three on the heavy (VH) chain, are responsiblefor binding to the antigen, i.e. for its antigen specificity. Theseloops are referred to as the Complementarity Determining Regions (CDRs).Because CDRs from both VH and VL domains contribute to theantigen-binding site, it is the combination of the heavy and the lightchains, and not either alone, that determines the final antigenspecificity.

An “antibody fragment” contains at least one antigen binding fragment asdefined above, and exhibits essentially the same function andspecificity as the complete antibody of which the fragment is derivedfrom. Limited proteolytic digestion with papain cleaves the Ig prototypeinto three fragments. Two identical amino terminal fragments, eachcontaining one entire L chain and about half an H chain, are the antigenbinding fragments (Fab). The third fragment, similar in size butcontaining the carboxyl terminal half of both heavy chains with theirinterchain disulfide bond, is the crystalizable fragment (Fc). The Fccontains carbohydrates, complement-binding, and FcR-binding sites.Limited pepsin digestion yields a single F(ab′)2 fragment containingboth Fab pieces and the hinge region, including the H-H interchaindisulfide bond. F(ab′)2 is divalent for antigen binding. The disulfidebond of F(ab′)2 may be cleaved in order to obtain Fab′. Moreover, thevariable regions of the heavy and light chains can be fused together toform a single chain variable fragment (scFv).

Pharmaceutically acceptable salts are for example acid addition saltsand basic salts. Acid addition salts are e.g. HCl or HBr salts. Basicsalts are e.g. salts having a cation selected from alkali or alkaline,e.g. Na+, or K+, or Ca2+, or an ammonium ion N+(R1)(R2)(R3)(R4), whereinR1 to R4 independently of each other mean: hydrogen, an optionallysubstituted C1-C6-alkyl group, an optionally substituted C2-C6-alkenylgroup, an optionally substituted C6-C10-aryl group, or an optionallysubstituted C6-C10-heteroaryl group. Further examples ofpharmaceutically acceptable salts are described in “Remington'sPharmaceutical Sciences” 17. ed. Alfonso R. Gennaro (Ed.), MarkPublishing Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia ofPharmaceutical Technology.

Pharmaceutically acceptable solvates are for example hydrates.

A tubular clutch 90 is provided between the display member 60 and thebutton 70. The clutch is fixed relative to and retains the button 70 andtogether they travel axially relative to the proximal drive sleeve 42when the button 70 is depressed during dispense, disengaging the clutchteeth from the dial sleeve 62. It also transfers torque from the buttonto the proximal drive sleeve 42, and the dialing and 0 U/80 U stop loadsfrom the button via the clutch teeth to the dial sleeve and numbersleeve.

Drive sleeve splines 91 provided on an inner surface of the clutchengage with the proximal drive sleeve 42. At the distal end face, clutchbiasing teeth 92 are provided which mate with similar teeth on theproximal clicker part 102 to ensure that in the button out position(dialed dose) the clutch is locked in rotation to the proximal clickerpart 102 under the biasing action of the clutch spring 103. The teeth 92are shallow in height to prevent the proximal clicker part 102 fromengaging with splines on the proximal drive sleeve 42 during dialing.Four snap apertures 93 serve to retain the snap features 74 of button70. Near its proximal end, the clutch has splines 94 which at the end ofdispense with the button 70 depressed lock to the inner body 20 toprevent the user from rotating the button 70 below the 0 U position.

Clutch teeth 95 engage with clutch teeth 65 of the dial sleeve torotationally couple the button 70 via the clutch to the number sleeve61. During dispense the clutch is moved axially so as to disengage theseclutch teeth 95 releasing the dial sleeve 62 to rotate back into thedevice whilst the clutch 90 and hence driver 40 move axially to dispensethe dose.

The clicker 100 comprises a distal clicker part 101, a proximal clickerpart 102 and a spring 103. The clutch spring 103 serves to bias thebutton 70 out so that at the end of a dose the button 70 pops out,re-engaging the clutch 90 with the dial sleeve 62 ready for dialing.Further, it provides the spring force for the clicker components to actas clickers and also as detent positions for the number sleeve 61. Inaddition, it holds the two halves of the drive sleeves 41, 42 inrotational engagement during dialing and dispense, whilst allowing themto disengage during device reset.

The distal clicker part 101 is permanently splined to the proximal drivesleeve 42 and engages with the proximal clicker part 102 which in turnis splined to the inner body 20. During dialing when the drive sleeve isrotated relative to the inner body, the two clickers 101, 102, rotaterelative to each other under the compression force of the clutch spring103. This force combined with the clicker teeth formed on the end faceof each clicker provides the clicks and also the detent dialingpositions.

During dispense the two clickers 101, 102 are pressed together under thedispense load and therefore prevent relative rotation between theproximal drive sleeve 42 and inner body 20, driving the piston rodforwards to deliver the dose. The splines 104 on the inner borerotationally couple the distal clicker part 101 to the proximal drivesleeve 42 at all times, but allow free axial movement when the button 70is depressed during dispense and when the two clickers ride over eachother during dialing. The profile of the clicker teeth 105, 106 on bothdistal clicker part 101 and proximal clicker part 102 are identical andride over each other under the compressive load from the spring 103during dialing.

The proximal clicker part 102 is permanently splined to the inner body20 by external splines 107 which prevent relative rotation with theinner body during both dialing and dispense, providing clicks duringdialing and locking the proximal drive sleeve 42 in rotation duringdispense. Additional cylindrically shaped splines 108 also couple theproximal clicker part 102 rotationally to the proximal drive sleeve 42when the button 70 is depressed, this preventing the user from dialingpast 80 units with the button depressed. Proximal clicker part 102, inaddition to the primary clicker teeth 106, has clutch biasing teeth 109on the opposite end face. These teeth mate with similar teeth 92 on theclutch to ensure that in the button out position (dialed dose) theclutch is locked in rotation to the proximal clicker part 102 under thebiasing action of clutch spring 103.

The cartridge bias spring 110 is assembled as two components one afterthe other, the lower first and the upper second. The spring combinationserves to apply an end load to the cartridge 81 at extremes of toleranceso as to bias it forwards onto the end face of the ferrule in thecartridge holder 80. This ensures that when the user removes andattaches a needle, the friction between the needle cannula and septum ofthe cartridge does not move the cartridge 81 axially relative to thecartridge holder 80. The bias spring 110 also acts to provide a forceagainst which the user has to connect the cartridge holder 80 and thismay add to the tactile feedback of this bayonet joint. The spring 100also serves to eject the cartridge holder 80 if the cartridge holder isnot rotated into a secure position, highlighting this error to the user.

The cap 120 serves to protect the cartridge holder 80 from damage andthe cartridge 81 itself from dust dirt ingress on to the area around theseptum. The cap 120 is designed to accommodate a standard pen injectorneedle. The cap 120 comprises a clip element 134 or fixing element forattaching the cap 120 and, hence, the drug delivery device 1 to afurther element, e.g. a jacket pocket of the user. Preferably, the clipelement 134 is snap-fitted to the cap 120. Details concerning thestructure of the cap 120 and the clip element 134 as well as theirconnection are described later on.

The window insert 230 may include a lens to magnify the dose numberse.g. by approximately 25% from their printed size. The window insert 230may be back printed to protect the printed surface from abrasion andalso to maximize the light entering through the window aperture, givinguniform illumination of the dose numbers and white area around thesenumbers. Arrows may be printed adjacent to the window aperture thatindicate the dose dialed.

In the following, the function of the drug delivery device and itscomponents will be explained in more detail with reference to FIGS. 17to 19.

To use the device, a user has to select a dose. In the start (at rest)condition as shown in FIG. 17 the display member 60 indicates the numberof doses dialed to the user. The number of dialed units can be viewedthrough the dose window 230 in the outer body 10. Due to the threadedengagement between the display member 60 and the inner body 20 rotationof the button 70 in a clockwise fashion causes the display member 60 towind out of the device and incrementally count the number of units to bedelivered. FIG. 18 shows an intermediate stage of dialing (e.g. 7 of 80units).

During dose setting button 70, driver 40 and display member 60 arerotationally locked together via clutch 90. Further, button 70, driver40 and display member 60 are axially coupled. Thus, these threecomponents wind out of the outer housing 10 during dose setting.Clockwise rotation of the button 70 causes the driver 40 to rotate andin doing so it advances along the piston rod 30 which remains fixedthroughout dialing. The clicker arrangement 100 provides tactile andaudible feedback to the user when dialing doses. At the maximum settabledose of 80 units, the stop features 12 and 67 engage to prevent furtherdialing.

The last dose nut 50 provides the function of counting the number ofdispensed units. The nut 50 locks the device at the end of cartridgelife and as such no more drug can be dialed by the user. The last dosenut 50 and the driver 40 are connected via a threaded interface asexplained above. Further, the last dose nut 50 is assembled into splines22 such that the nut 50 and the inner body 20 are rotationally lockedtogether (at all times). Rotation of the driver 40 during dialing causesthe nut 50 to advance along the thread 44. The nut 50 is free to slideaxially within the inner body 20 at all times which allows advancementof the nut. The change in pitch of thread 44 shown in FIG. 9 towards thefinal doses axially accelerates the advancement of the nut 50 towardsthe end of cartridge life lockout condition. At the end of lifecondition, the stop features 51 of the last dose nut 50 contact thecorresponding features 45 on the driver 40. The splined contact withinner body 20 reacts any torque transmitted by these stop features 45.

With the desired dose dialed, the device 1 is ready for dose dispensing.This basically requires pushing button 70 which will result in adisengagement of the clutch 90 from dial sleeve 62 thus allowingrelative rotation between the display member 60 and the button 70. Inall conditions the driver 40 and the button 70 are rotationally lockedtogether by engagement of arms 73 and fingers 48 and by splines 91engaging corresponding splines on proximal drive sleeve 42. Thus, withthe clutch 90 disengaged (button 70 pushed in) button 70 and driver 40are rotationally locked together with the button 70, the driver 40 andthe display member 60 still being axially coupled.

When dispensing a dose, the dose button 70 and clutch 90 are movedaxially relative to the mechanism compressing the clutch spring 103.Because the proximal clicker part 102 is splined to the inner body 20and the axial load passing through the clicker teeth 105, 106 locks thedistal clicker part 101 in rotation to the proximal clicker part 102,the mechanism is forced to move axially whilst the dial sleeve 62 andnumber sleeve 61 are free to spin back into the outer housing 10. Theinteraction of mating threads between the piston rod 30, driver 40 andinner body 20 delivers a mechanical advantage of 2:1. In other words,axially advancing driver 40 causes the piston rod 30 to rotate which dueto the threaded engagement of piston rod 30 with the inner body 20advances the piston rod. During dose dispensing dispense clicker 68, 71is active which involves button 70 and display member 60. The dispenseclicker provides primarily audible feedback to the user that drug isbeing dispensed.

The end of this step is shown in FIG. 19. At this point the dose iscomplete and when the user removes the force from the end of the dosebutton 70, the clutch spring 103 pushes this dose button 70 rearwards,re-engaging the teeth 65 and 95 between the clutch and the dial sleeve.

Resetting the device starts with removal of the cartridge holder 80 andreplacing an empty cartridge with a full cartridge 81. As the cartridgeholder is re-attached, the bung of the new cartridge contacts bearing31, thus pushing piston rod 30 back into the housing. Initially, thepiston rod 30 screws into the inner body 20, thereby axially disengagingthe coupler 43 from the proximal drive sleeve 42 against the biasingforce of spring 103. Once disengaged the coupler 43 is free to startrotating together with distal drive sleeve 41 and continues to do so asthe cartridge holder 80 is moved axially into engagement with the innerbody 20. Thus, the distal drive sleeve 41 rotates with respect to theproximal drive sleeve 42 which is still rotationally constrained ininner body 20 as clicker parts 101 and 102 are pressed together bycompressed spring 103. As the distal drive sleeve 41 rotates, last dosenut 50 is reset to its (distal) start position. Coupling the cartridgeholder 80 to inner body 20 backs off the mechanism due to the bayonetstructure 23 allowing re-engagement of the proximal drive sleeve 42 withcoupler 43 and thus the distal drive sleeve 41.

In the following the cap or cap assembly 120 is described in moredetail. An embodiment of the cap is shown in FIGS. 20 to 25.

The cap 120 has a distal end 121 and a proximal end 122. It serves tocover and protect the cartridge holder 80 from damage and the cartridge81 itself from dust and dirt ingress on to the area around the septum.The cap 120 is designed to accommodate a distal part of the pen injectorwhich is moved into the cap 120 through a proximal opening of the cap120. The cap 120 may be attached to the remainder of the drug deliverydevice 1 in such a manner that the needle arrangement 180 attached tothe cartridge or to the cartridge holder and the cartridge holder 80 arelocated inside the cap 120, in particular, when the cap is fixed to theremainder of the device. The cap 120 is detached before use of the drugdelivery device 1, such as to set and/or dispense a dose of drug. Theinterior of the cap 120 is formed such that there is enough space forthe needle arrangement 180 attached to the cartridge and the cartridgeholder 80. The cap may be configured such that it covers the remainderof the device on all sides, when it is attached. The proximal opening ofthe cap may be the only opening of the cap. Means (not shown) forguiding and holding the cartridge holder 80 and the needle arrangement180 may be provided on the inner surface of the cap 120.

FIG. 20 shows an exploded view of the cap 120 comprising an outer capelement 130 and an inner cap element 131. Furthermore, the clip element134 is shown. The inner and outer cap elements and, preferably the clipelement, form together a cap assembly 200, which is described later onin detail. The outer and inner cap elements 130, 131 are formed by ormade by a metal sleeve and a plastic sleeve, respectively. The sleevescan be assembled together to form the removable cap 120. The outer andinner cap elements 130, 131 are connected by suitable means, e.g.adhesive means, positive locking, friction locking and/or a snapinteraction. The clip element 134 allows connection of the injector pen1 by means of the cap 120 to a shirt or jacket pocket and is alwayshandy for that reason. An aperture 135 in the outer cap element 130enables the clip element 134 to cooperate with, such as to snap to, theinner cap element 131.

The outer cap element 130 is preferably made of metal or of a metalalloy; the inner cap element 131 is preferably made of plastic. Thecombination of the metal outer cap element 130 and the plastic inner capelement 131 provides a high-quality look and pleasant touch. Also, themetal outer cap element 130 provides a hard wearing exterior surface ofthe device. The cap 120 is not too heavy and allows comfortablehandling. The design of the inner component of the cap 120 allowsretaining the clip element 134 and provides sufficient space toaccommodate a standard needle and needle cover fitted to cartridgeholder 80 inside the cap 120, in particular, when the cap is attached tothe cartridge holder or another part of the device.

The outer cap element 130 may be a 0.4 to 0.6 mm thick aluminium elementthat provides a metal skin over the polymer inner cap element 131. Theform of the cap 120 may be similar to that of a cap completely made ofplastic. Such a cap 120 may substitute a cap completely made of plasticwith no change in the tactile feel during attachment. Similar plasticfeatures of the inner cap element 131 will not increase the risk of wearthat may otherwise occur if attaching a plain metal sleeve to theexisting plastic cartridge holder retention features.

The inner and outer cap elements 131, 130 are sleeve-shaped. The metalsleeve can be deep drawn from a metal sheet and then anodised over atleast the outer surface. The anodising provides a high quality and hardwearing exterior surface to the cap 120 and enables the cap 120 to begiven a variety of metallic colors. The removable cap 120 comprising themetal outer cap element 130 and the plastic inner cap element 131 canthen be attached to a pen housing/mechanism which may be also made witha similar metal sleeve, to provide a reusable injection device that hasa high quality visual appearance and a robust surface.

This design minimises cost and provides robust hard-wearing features.Hence the use of a combination of metal and plastic sleeve-shapedcomponents enables the plastic sleeve to be moulded with features thatattach to the plastic cartridge holder cap retention means. The capretention means of the cartridge holder and/or of the cap assembly maybe provided in the proximal section of the respective component.

FIG. 21 shows a sectional view of a proximal region of the outer capelement 130. FIG. 22 shows a three-dimensional cut-out view of thiscomponent. The outer cap element 130 is formed by a metal sleeve deepdrawn with reduced thickness at the open end section. The very proximalregion is rolled over to form a rounded or folded end 161. Such rollingback of the material may form a beading. In this embodiment the materialof the outer cap element 130 has been bent once. Nevertheless, thematerial may be bent more than once. Such bending means that sharp edge147 is on the inner surface of the outer cap element 130 and thereforeis not accessible by the user.

Due to the thinner material of the open end, which is created during thedeep drawn process, and then forming the beading, a circumferentialrecess 143 is formed on the inner surface of the outer cap element 130.This recess 143 serves as space into which the inner cap element 131 candeform when attaching the cap 120 to the cartridge holder 80. The sharpedge 147 is the proximal edge of the recess 143, the edge 147 serving toretain the plastic inner cap element 131 after assembly.

FIG. 23 shows a sectional view of a proximal section 141 of the cap 120during attachment to the drug delivery device 1. During attachment thecap 120 including the inner and outer cap elements 131, 130 movesproximally with respect to the cartridge holder 80 in such a manner thatthe cartridge holder 80 moves into the cap 120.

The outer cap element 130 has a proximal section 141 comprising a cavity143 on the inner surface of the outer cap element 130. The cavity 143 isformed as a circumferentially running recess in this embodiment.Alternatively the cavity 143 may have another form which may correspondwith the form and size of the deformable region 151 of the inner capelement 131.

The thickness of the outer cap element 130 in the region of the cavity143 is smaller than the thickness of a distal section or a middlesection of the outer cap element 130. The distal edge 145 of the cavity143 is formed in the shape of a ramp which allows a gentle transitionbetween the middle section of the outer cap element 130 and the cavity143 located in the proximal section 141. The proximal edge 147 of thecavity 143 is steeper than the distal edge 145 and may be formed as asharp edge.

The inner cap element 131 comprises cap snap means 149 located on theinside of a proximal section of the inner cap element 131 and suitablefor engaging with a cap retention means 155 located on the cartridgeholder 80 of the drug delivery device 1. The cap snap means 149 isformed by at least a proximal part of the deformable region 151 that maybe deformed during attachment and detachment in order to lock the capsnap means 149 to the cap retention means 155 of the drug deliverydevice 1 and to release the cap snap means 149 from the cap retentionmeans 155. The cap snap feature 149 comprises a raised internal bumpfeature 153 or finger and a cavity 171 where the inner cap element 131in the region of the cavity 171 is thinner than in other regions; thecavity 171 may be formed by the deformable region 151. The internal bumpfeature 153 has a proximal slope being less steep than a distal slope.

The reduced thickness of the inner cap element's cavity 171 enables thedeformation of the cap snap means 149, thereby allowing engaging to thecap retention feature 155. Due to the cavity 143 of the outer capelement 130 there is a gap between the outer and inner cap elements 130,131. The deformable region 151 is deformable into the cavity 143 of theouter cap element 130. In other words, the deformable region 151 isdeformable into the gap between the outer and inner cap elements 130,131.

According to one embodiment, the proximal end 173 of the cap snap means149 extends proximally over the proximal edge 147 of the cavity 143; theproximal edge 147 preventing outwards movement of the proximal end 173of the cap snap means 149 and to hold this end circular. According to afurther embodiment, the proximal end 173 of the cap snap means 149 doesnot protrude over the edge 147. In particular, there may be no need forthe proximal end 173 to protrude over the edge 147 as the clip holdsboth cap parts together axially.

The cap retention means 155 is located on the outer surface of theplastic cartridge holder 80. The cap retention means 155 comprises anelevation 157 which may have a base area formed as trapezium, circle,triangle or any other shape. In one embodiment two elevations 157 may bearranged on opposite sides of the cartridge holder 80, as shown in FIGS.3 and 6. In one embodiment there are two or more than two elevationsthat are arranged equally or non-equally spaced on the drug deliverydevice 1.

The elevation 157 has proximal and distal slopes; the latter being lesssteep than the proximal slope of the elevation 157. The distal slopeenables easy sliding of the proximal slope of the internal bump feature153 over the top of the elevation 157 during attachment. The steeperslopes of both the elevation 157 and the internal bump feature 153hinder distal movement of the internal bump feature 153 once it hasmoved over the top of the elevation 157, thereby preventing backwardmovement of the internal bump feature 153 after attachment. However, theapplication of a sufficient force by the user pulling the cap 120distally pulls the internal bump feature 153 over the elevation 157again, thereby allowing detachment of the cap 120. Since the distalslope of the internal bump feature 153 and the proximal slope of theelevation 157 are steeper, the force required for detachment is higherthan for attachment, which prevents accidental detachment of the cap120. Nevertheless, alternative internal bump feature 153 and elevation157 embodiments may have other slope designs, which may be symmetrical.

When the internal bump feature 153 slides over the elevation 157, theinternal bump feature 153 is pushed towards the outer cap element 130.Since the proximal end 173 of the cap snap means 149 is held in itsposition by the proximal edge 147 of the outer cap element 130, theresulting torque deforms the deformable region 151 outwardly and allowsthe nose tip to slide over the elevation 157. The cavity 143 of theouter cap element 130 allows space to accommodate at least some of thedeformation of the plastic inner cap element 131 when the internal bumpfeature 153 slides over the elevation 157 during attachment of the cap120.

FIG. 24 shows a sectional view of the proximal section of the cap 120after attachment to the drug delivery device 1.

The internal bump feature 153 is engaged behind the proximal edge of theelevation 157. The elevation 157 engages to the cavity 171 of the innercap element 131. Though the internal bump feature 153 has slid over theelevation 157, the cap snap feature 149 is still deformed into thecavity 143 of the outer cap element 130. The combination of the proximaledge 147 of the outer cap element 130 holding the proximal end 173 ofthe cap snap means 149 in its position and the elevation 157 pushing thedeformable region 151 into the cavity 143 of the outer cap element 130cause a close or interference fit of the cap snap feature 149 over theelevation 157, thereby holding the cap 120 in the attached position.

FIG. 25 shows a sectional view of the proximal section of anotherembodiment of cap 120 after attachment to the drug delivery device 1.

This embodiment differs from the one described above by the design ofthe inner cap element 131. The proximal end 173 of the cap snap means149 does not extend over the proximal edge of the cavity 143, whichallows a deformation in such a manner that the proximal edge 173 alsomoves into to the cavity 143 during attachment. In this embodiment thecap snap means 149 are able to deform more readily with less force inputrequired from the elevation 157.

The features of the embodiments mentioned above may be combined. Thelayout, function, and number of components may be changed in otherembodiments.

In the following, the clip element 134 is described in more detail withreference to FIGS. 26 to 39.

FIGS. 26 and 32 show the clip element 134 or fixing element of the drugdelivery device 1. By means of the clip element 134, a fixation orattachment of a cap, e.g. the previously described cap 120 or a capassembly 200 (see also below) of the drug delivery device 1 or the drugdelivery device 1 may be fixed to a further component. The clip element134 comprises a fixing portion 168 or main body with an elongate shape(see FIG. 31). Moreover, the clip element 134 comprises a slightcurvature at a distal end (on the left in FIG. 26) of the clip element134.

The clip element 134 comprises two components, i.e. a first component300 and a second component 301 (see FIGS. 31 to 38, for example). Eachone of the first and the second component 300, 301 is integrally formed.This may mean that the first and the second component 300, 301 aresingle-piece components. The first and the second component 300, 301 areattached, preferably non-releasably attached, to one another. The secondcomponent 301 is adapted and arranged to at least partly receive thefirst component 300. In particular, the first component 300 is at leastpartly introduced into the second component 301. Thus, the secondcomponent 301 may provide an outer shell of the clip element 134.

The first component 300 is at least in parts flexible and/or elasticallydeformable. In particular, the first component 300 comprises a flexiblesection. The flexible section provides a local radial flexibility of thefirst component 300 enabling the attachment of the clip element 134 to afurther component, e.g. a jacket pocket. The first component 300comprises plastic. In particular, the first component 300 is a plasticcomponent. This may provide a certain degree of elastic deformability ofthe first component 300 per se. The first component 300 is injectionmoulded, for example.

In section, the first component 300 has an I-like shaped region (see,for example, FIG. 37). One horizontal stroke or bar of the “I” may,thereby, at least in parts be received by the second component 301(upper horizontal stroke in FIG. 37). In the following, this stroke isreferred to as “the upper horizontal stroke”. The upper horizontalstroke may constitute the previously mentioned main body or elongatedbody 168. A further horizontal stroke or bar of the “I” may be receivedby the previously mentioned cap 120, which is described later on in moredetail. A vertical stroke or bar of the “I” may connect the twohorizontal strokes.

The first component 300 comprises a tip 303 (see FIGS. 38 and 39, forexample). The tip 303 is arranged in a proximal end section of the clipelement 134. The tip 303 may constitute the very proximal region of thefirst component 300. In particular, the tip 303 may constitute theproximal end of the upper stroke of the “I”.

In the proximal end section, a thickness or radial extension of thefirst component 300 reduces towards its very proximal end. Accordingly,the tip 303 comprises a reduced thickness as compared to furthersections of the first component 300, e.g. a distal section or a middlesection. In other words, the tip 303 is thinner or has a reduced radialextension as compared to the remainder of the first component 300. On anupper side of the tip 303, i.e. that side, which faces the secondcomponent 301, the tip 303 may be slightly sloped. The thin tip 303enables the first component 300 to flex locally in this region, asmentioned above.

The second component 301 may be made of a rigid material. In particular,the second component 301 may comprise a material which is more rigidthan the material of the first component 300. The second component 301may comprise or be made of metal or a metal alloy, e.g. steel oraluminium. The second component 301 may completely consist of metal. Inthis embodiment, the second component 301 may be stamped from a sheet ofmetal and then plated. In an alternative embodiment, the secondcomponent 301 may comprise fibreglass. The second component 301 maycompletely consist of fibreglass.

The second component 301 comprises an elongate shape having roundededges. The second component 301 comprises a shape which is adjusted tothe shape of an upper side of the first component 300 such that thesecond component can at least partly receive and/or cover the firstcomponent 300. The second component 301 comprises folded over edges orside walls. The folded over side walls may comprise a radial extensionor height similar or equal to a thickness of one of the horizontalstrokes of the previously described “I” (see FIG. 37). The secondcomponent 301 further comprises a curvature in a distal end section. Bymeans of the rigid and hard material of the second component 301, a highquality and hard-wearing exterior surface of the clip element 134 isprovided. In the embodiment where the second component 301 comprisesmetal, the second component 301 can further be given a variety ofmetallic colors.

The second component 301 further comprises a cavity or clearance region304 (see FIG. 39). The cavity 304 is arranged on the underside of thesecond component 301, i.e. that side of the second component 301 whichfaces the first component 300 when the components 300, 301 are attachedto one another. The cavity 304 is delimited by the folded over sidewalls. The design of the tip 303 allows it to flex into the cavity 304of the second component 301, thus replicating a pinching effect of astandard pocket clip. In this way, a measure of retention is providedwhen the cap 120 and, hence, the device 1 is placed into a pocket orsimilar.

The first and second component 300, 301 are firmly connected to oneanother. Preferably, the first and the second component 300, 301 arenon-releasably connected to one another. The second component 301 ispress fitted to or clipped onto the first component 300. In particular,the second component 301 is press-fitted over the first component 300,thus providing a robust and hard-wearing shell for the first component300.

The second component 301 comprises a retaining feature 302, which isshown in FIGS. 33, 36 and 37, for example. The retaining feature 302 mayextend along the whole length of the second component 301. The retainingfeature 302 may comprise the previously mentioned side walls of thesecond component 301. The fold over of the respective side wall isgreater than 90 degrees with respect to a lateral axis of the clipelement 134. The fold over may be 91, 92, 93, 94, 95, 100 or 105degrees, for example. The folded over side walls do not contact anunderside of the second component 301, wherein the underside may be thatside of the second component 301 facing and/or receiving the firstcomponent 300 when the clip element 134 is assembled.

The folded over side walls of the second component 301 delimit an innerspace of the second component in which the first component 300 is partlyreceived when assembling the clip element 134. For coupling the firstcomponent 300 and the second component 301 to one another, in particularfor clipping the second component 301 onto the first component 300, thefirst component 300 is partly or wholly introduced into the secondcomponent 301. An upper side of the first component 300 is receivedbetween the folded over side walls of the second component 301. Inparticular, the upper horizontal stroke of the “I”-shaped firstcomponent 300 is introduced over its whole length between the foldedover side walls 302 of the second component 301. The folded over sidewalls of the second component 301 thereby keep the first component 300in a predefined position with respect to the second component 301. Thedesign of the components 300, 301 allows for an elastic deformationespecially of the second component 301 when the first component 300 isinserted past the folded over side walls. The second component 301 formsa C-section when viewed in cross section (see FIGS. 36 and 37). Thisallows a relatively large amount of flexibility of the tips of the, C′,when the second component 301 is clipped onto the first component 300.The first component 300 acts as a solid block in compression. Onceinserted, the second component 301 may spring back for retention. Due tothe fold over of the side walls being just greater than 90 degrees, thesecond component 301 is firmly retained once press-fitted over the firstcomponent 300.

However, before the second component 301 and the first component 300 areconnected to one another as described above, the first component 300 ofthe clip element 134 is secured to the cap 120. For securing the clipelement 134 and, in particular the first component 300, to the cap 120,the first component 300, comprises a guiding element 150, which can beseen from FIGS. 26 and 31, for example. The guiding element 150 isdisposed in a distal end section of the first component 300 at an insideof the above mentioned curvature. The guiding element 150 is arranged onan underside of the first component 300 facing away from the secondcomponent 301. The guiding element 150 may constitute or comprise a railsuch that the clip element 134 may be guided by an element receiving theguiding element 150, preferably, along a longitudinal axis of the clipelement 134 or the device 1.

The guiding element 150 extends over less than half of the axialextension of the first component 300 of the clip element 134. Theguiding element 150 comprises a T-shaped cross-section for facilitatingthe mentioned guiding functionality (see also FIG. 29). In order to formthe T-shaped section, the guiding element 150 comprises a receivingportion 152 (see FIG. 26). The receiving portion 152 may constitute thehorizontal stroke or bar of the “T” of the T-shaped section. Preferably,the receiving portion 152 is configured to be received by one or moreopenings or apertures of the components to which the clip element 134 isto be mounted, e.g. in a cap assembly 200 (see FIGS. 29 and 30).

Furthermore, the guiding element 150 comprises a guiding portion 158(see FIG. 26). The guiding portion 158 constitutes the vertical strokeor bar of the “T” of the T-shaped section of the guiding element 150.The guiding portion 158 may be a web connecting the elongated main body(upper horizontal stroke of the “I”) of the first component 130 with thereceiving portion 152. The guiding portion 158 may further be receivedby or arranged in one or more openings of the components to which theclip element 134 is to be mounted, e.g. in the mentioned cap assembly200.

The clip element 134, particularly the guiding element 150, comprises aconnection feature 154. The connection feature 154 comprises orconstitutes a protrusion protruding radially at the underside of thefirst component 130. Preferably, the connection feature 154 isconfigured to interact with a corresponding connection feature 170, e.g.of an inner part or cap element 131 (see FIG. 28) for connecting thefirst component 300 and the cap 120. The connection feature 154 isdisposed in a proximal end section of the guiding element 150. Theconnection feature 154 may further comprise or constitute a distal faceof the guiding element 150. The connection feature may be designed toestablish a snap fit connection to the inner cap element 131

The first component 300 further comprises a feature 156. The feature 156comprises a radial face with a normal perpendicular to the longitudinalaxis (not explicitly indicated) of the first component 300 and alongitudinal face which is designed to hide or cover over any gapsbetween the first component 300 of the clip element 134 and the outerpart 130 resulting from tolerances in manufacture and assembly. Thefeature 156 is designed to be in small amount of clearance rather thanabutting in nominal tolerance conditions. In particular, the feature 156may be configured to be in small amount of clearance to one or morecorresponding components to which the clip element 134 is to be mounted,e.g. in the cap assembly 200 (see FIG. 30).

Moreover, the clip element 134, in particular the first component 300,comprises an attachment feature 160. The attachment feature 160 may beconfigured to interact with a further component (see depression 166 inFIG. 27). The attachment feature 160 comprises a bump or pip. Theattachment feature 160 is axially spaced from the guiding element 150and arranged near a proximal end of the first component 300 and/or theclip element. The attachment feature is arranged on the underside of thefirst component 300 facing away from the second component 301. Theattachment feature 160 is, preferably, configured to interact with theouter part 130 by means of mechanical contact, or close proximity tocreate a ‘pinch point’. Thereby, fixation or attachment of the capassembly 200 or drug delivery device 1 to the further element, such as ashirt pocket of a user of the assembly 200 or the device 1 may befacilitated or aided. Particularly, said mechanical contact may increasethe friction or the grip force and, therewith, the reliability of theattachment of the cap assembly 200 to the further element.

FIG. 27 shows a perspective view of an outer part or outer cap element130 which may be or relate to the above-mentioned outer cap element. Theouter part 130 comprises an elongate shape. The outer part 130 furthercomprises a sleeve-like shape. Preferably, the outer part 130 is made ofa metal, e.g. from aluminium. To this effect, the outer part 130 is,preferably, formed or fabricated by deep drawing (as mentioned above).The outer part 130 further comprises the previously mentioned opening164. The opening 164 is arranged at a distal end of the outer part 130.The opening 164 is, preferably, formed from the outer part 130 bypunching. The outer part 130 may further comprise a proximal openingwhich is not explicitly indicated in FIG. 27.

Formed within the opening 164 is a corresponding guiding feature 162corresponding to the guiding element 150 described by means of FIG. 26.The corresponding guiding feature 162 extends—originating from theopening 164—in a proximal direction of the outer part 130. Thecorresponding guiding feature 162 may be a guide slot. The correspondingguiding feature 162 may be configured to receive the guiding portion 158of the guiding element 150 such that the guiding portion 158 is arrangedinside the corresponding guiding feature 162. Preferably, the opening164, the corresponding guiding feature 162 and the clip element 134 areconfigured such that the guiding element 150 can be introduced in orreceived by the opening 164. When, in particular after introduction ofthe guiding element 150 into the opening 164, —e.g. during an assemblyof the cap assembly 200—the first component 300 is pushed proximally,the guiding portion 158 may be received by or arranged in thecorresponding guiding feature 162, wherein the receiving portion 152 is,preferably, only received by the remainder of the opening 164 andarranged inside the outer part 130 and/or the inner part 131 (see FIGS.29 and 30).

The outer part 130 further comprises the previously mentioned depression166. The depression 166 receives or interacts with the above-mentionedattachment feature 160 of the clip element 134 when, e.g., the firstcomponent 300 and the outer part 130 are assembled (see FIGS. 29 and 30below). Preferably, the attachment feature 160 extends into thedepression 166 and/or contacts the outer part 130 in the depression 166.The depression 166 is axially, particularly proximally, spaced from theopening 164 along a longitudinal axis of the outer part 130. Preferably,the depression 166 is shaped according to the attachment feature 160,i.e. with similar curvature as the mentioned bump of the attachmentfeature 160 (see FIG. 26).

FIG. 28 shows a perspective top view of an inner part 131. The innerpart 131 may be a sleeve and configured to be introduced in the outerpart 130. The inner part 131 comprises a corresponding connectionfeature 170. The corresponding connection feature 170 corresponds to theconnection feature 154 of the first component 300 such that the firstcomponent 300 can be connected to the inner part 131 by an interactionof the connection feature 154 and the corresponding connection feature170 (see FIG. 30). The corresponding connection feature 170 mayconstitute or comprise a proximal face of the inner part 131. The innerpart 131 further comprises an opening 172. The opening 172 is arrangedat or near the distal end of the inner part 131. The opening 172 mayfurther be shaped similar to the opening 164 of the outer part (see FIG.27). Formed within the opening 172 is a corresponding guiding feature172 a corresponding to the guiding element 150.

FIG. 29 shows a schematic section of parts of a cap assembly 200 (seealso FIG. 30). The assembly 200 comprises the previously described clipelement 134 and the outer part 130 and the inner part 131. FIG. 29 showsthe mentioned components in an assembled state. An inner side of the capassembly 200 is shown at the bottom and an outer part is shown at thetop of the section shown in FIG. 29. In the depicted situation, theinner part 131 is arranged in the outer part 130 and at least a sectionof the clip element 134 and/or the guiding element 150 extends throughthe opening 164 of the outer part 130 and, preferably, also through theopening 172 of the inner part 131. To this effect, the openings 164 and172 may overlap in the cap assembly 200. It is further shown in FIG. 29that the guiding element 150 comprises the T-shaped section (said “T” isdepicted upside down), as described above. The section of the wholefirst component 300 may, thereby, be shaped I-like, as described above.The guiding portion 158 is arranged in the corresponding guiding feature162 (see also FIG. 29). The guiding element 150, particularly thereceiving portion 152 may prevent an (outward) radial movement of theclip element 134 with respect to the outer part 130 and/or the innerpart 131, for example. This is because the corresponding guiding feature162 is too narrow, as to allow for the receiving portion 152 to radiallypass or move through the corresponding guiding feature 162.

FIG. 30 shows a longitudinal section of parts of the cap assembly 200.The cap assembly 200 comprises a longitudinal axis X. The longitudinalaxis X may coincide or be collinear with the longitudinal axis of theclip element 134, the outer part 130 and/or the inner part 131. Also, adrug delivery device in which the cap assembly 200 is attached is shownin FIG. 30 which shows, e.g. the cartridge holder 180.

The clip element 134 closes the opening 172 of the inner part 131 andthe opening 164 of the outer part 130 such that a rounded shape of thecap assembly 200 results. The connection feature 154 is arranged atleast partly in the opening 164 of the outer part 130, as well as in theopening 172 of the inner part 131 (openings are not explicitly indicatedin FIG. 30). Particularly, the corresponding guiding feature 162 isconfigured to receive the receiving portion 152 of the guiding element150 such that the receiving portion 152 is arranged inside of the outerpart 130 and also inside the inner part 131.

The clip element 134, in particular its first component 300, and theinner part 131 are connected with one another. Particularly, theconnection feature 154 interacts with, preferably abuts, thecorresponding connection feature 170 via a snap interaction such thatthe clip element 134, in particular the first component 300, and theinner part 131 are connected with respect to one another. The clipelement 134 and the inner part 131 are, preferably, reliably connectedto one another, as the distal face of the connection feature 154 and theproximal face of the corresponding connection feature 170 abut. In orderto connect the mentioned components or during the connection, at leastone of the first component 300 and the inner part 131, may at leastslightly be deformed. The connection feature 154 blocks proximalmovement (i.e. to the right in FIG. 30) of the inner part 131 withrespect to the outer part 130 such that the inner part 131 is retainedwithin the outer part 130.

The previously mentioned feature 156 is—under nominal toleranceconditions—arranged in a small amount of clearance to a distal face ofthe inner part 131 and a distal face and a radial face of the outer part130 (faces are not explicitly indicated). Although this is notexplicitly indicated in FIG. 30, the attachment feature 160 of the clipelement 134, preferably, mechanically contacts or lies in closeproximity to the depression 166 of the outer part 130 (see descriptionabove).

Also further components e.g. of a drug delivery device, wherein the capassembly 200 may be applied to, are shown. Such components relate to acartridge or cartridge holder 180 which may retain a drug (notexplicitly indicated). Furthermore, an injection needle 182 is shownwhich is in fluid communication with the drug from the cartridge orcartridge holder 180. It is shown that the inner part 131 accommodatesthe needle 182, an inner needle cover and furthermore at least a sectionof the cartridge or cartridge holder 180.

The inner part may, advantageously, be designed to be mouldable by aninjection moulding process with simple open-shut injection mouldtooling. Thereby, it can be manufactured by a low-cost moulding process.

It should be acknowledged that all of the concepts disclosed above andbelow can be combined especially as far as they concern conceptsrelating to a cap or cap assembly. Further, the present disclosure maysometimes address the same elements with different expressions which, ofcourse, should not be understood as forming different elements merelybecause of the fact that they are addressed slightly differently herein.Specifically: The cap 120 (see FIG. 3) may be or relate to the capassembly 200. The cartridge or cartridge holder 180 may be or relate tothe cartridge 81 and/or to the cartridge holder 80. The metal element ofthe cap may be or relate to the outer part 130. The plastic element ofthe cap may be or relate to the inner part 131. The outer cap elementmay be or relate to the outer part 130. The inner cap element may be orrelate to the outer part 131. The aperture 135 may be or relate to theopening 164. Also, elements not explicitly mentioned in the enumerationabove may be addressed with different expressions.

It was discovered that, when assembling the cap assembly or cap asdisclosed in the previous embodiments, it is difficult to securecomponents of the cap, for example the inner and the outer cap element130, 131, with respect to each other reproducibly in a defined relativeangular orientation.

In the following, an embodiment of a cap or a cap assembly is disclosedwhich addresses this issue in conjunction with FIGS. 40 to 43. Therein,the cap assembly as well as a method of assembling the cap assembly aredescribed. The components of the cap assembly disclosed below can be theones as disclosed further above. Accordingly, features disclosed hereinbelow with respect to the cap assembly can also apply to the furthercaps or cap assemblies disclosed herein.

FIG. 40 shows components of the cap assembly in an unassembled state. Asis apparent from FIG. 40, the components for the cap assembly comprise afirst cap component, which is herein above and below also designated asinner cap element 131, and a second cap component, which is herein aboveand below also addressed as outer cap element 130. Further, the capcomponents for the cap assembly comprise a third cap component, which isherein above and below also referenced as clip element 134. The firstand second cap components are formed sleeve-like, where the first capcomponent is adjusted to be received in and secured to the second capcomponent.

For the assembling of the cap assembly as illustrated in FIGS. 42A and42B, for example the first cap component 131 can be arranged on afixture and the second cap component 130, e.g. a deep-drawn metalcomponent, is guided over the first cap component until a defined endposition is reached.

As can be seen in FIG. 40, the first cap component 131, which ispreferably an injection moulded plastic part, comprises a guide track401, e.g. a groove. The guide track is axially oriented. The guide trackis, preferably, arranged in a section of the first cap component 131,which is oriented axially. The guide track may run parallel oressentially parallel to the longitudinal axis X of the first capcomponent 131. Preferably, in the region with the axial guide track thecap component 131 does not or not significantly widen in the radialdirection along the axis X. In a different region of the cap component,e.g. a region 402 which axially overlaps with the region comprising theguide track and/or a non-overlapping region, the cap component,particular the exterior surface, may widen more in the radial directionas seen along the axis X than in the region with the guide track 401.

The guide track 401 is preferably provided in a region which is spacedfrom a distal end and/or from a proximal end of the first cap component131. That is to say the start and/or the end of the track may bearranged at a distance from the proximal end and/or from the distal endof the cap.

The guide track 401 may be offset in the proximal direction with respectto the opening 172 and/or the guiding feature 172 a which is provided ator near the distal end of the cap component. The guiding feature 172 ais intended for interaction with the third cap component, that is to saythe clip element 134, as disclosed further above. The guide track 401may also be distally offset from a proximal opening of the first capcomponent 131. The guide track and the guiding feature 172 a may bealigned with respect to each other. They may extend in a common plane.Preferably, the guide track 401 extends in the, preferably axial,direction predetermined by the guiding feature 172 a. As also disclosedfurther above, the third cap component 134 may be designed to be fixedto the first cap component by means of a snap-fit interaction providedbetween the third cap component and the first cap component 131, forexample.

The second cap component comprises a guide feature 403 (best seen inFIG. 42 A). The guide feature 403 is formed by a protrusion protrudingfrom an inner surface of the second cap component. The guide feature isarranged to interact with the guide track to form a guiding interface.The second cap component 130 further comprises the guiding feature 162which has already been discussed further above. The guiding featurecontinues opening 164 in the proximal direction. The guiding feature 162is axially oriented. It is expediently oriented in the same directionand or arranged at a corresponding angular position as the guide track401 and/or the guiding feature 172 a, when the two cap components 130and 131 have been assembled to each other.

The second cap component further comprises the depression 166 asdisclosed further above. The second cap component is preferablymanufactured by deep drawing. By means of a pressing operation thatoccurs as part of a multi-stage deep drawing process, the depression 166may be formed and in the region of the depression 166, on the interiorsurface of the second cap component, the protrusion forming the guidefeature 403 may be formed. The protrusion expediently has thecomplimentary shape of the depression, e.g. both may be of hemisphericalshape. Thus, guide feature 403 may have a curved surface which isdesigned to interact with a bearing surface or bearing surfaces of theguide track 401, e.g. side walls of a groove. When the third capcomponent 134 has been connected to the first cap component 131, a bumpor a pip 404 of the third cap component may be arranged within thedepression 166 (see FIG. 43).

The guiding feature 172 a may form the fixing guide track, which guidesthe fixing feature of the third cap component 134, for example theconnection feature 154 shown in FIG. 26, to the appropriate fixingfeature provided in the interior of the first cap component 131. Whenthe third cap component 134 has been fixed to the first cap component131, the second cap component 130 may be secured relative to theremaining two components of the cap.

The first and second cap components 131, 130 are expediently adjustedwith respect to one another such that their cross sections ensure thatthey can only be assembled to one another when they have a certainrelative angular position or orientation. Accordingly, by way of thecross sections, at least a certain kind of pre-alignment may beprovided. The pre-alignment expediently ensures at least that the guidefeature 403 and the guide track 401 can be brought into cooperation. Forexample, the outer cross section of the first cap component and theinner cross section of the second cap component may be adjusted in theirshapes to suit or match one another such that they can only be assembledor moved axially relative to one another when they have the correctorientation. The cross sections are, for this purpose, expediently notcircular but rather designed to form a rotationally constrainedinterface between the two cap components. Therefore, it is expedient, tomatch the outer surface of a cross section of a region 404 of the firstcap component to the inner surface of a cross section of a region 405 ofthe second cap component. The regions 404 and 405 may be arranged suchthat the surfaces do cooperate, e.g. to form the rotationallyconstrained interface, during the assembling process, before the guidinginterface is established. For example, the region 405 may be arrangedproximally offset from the guide feature 403 and the region 404 may bearranged distally offset from the distal end of the guide track 401.

The guide track 401 may, for example in its distal end region 406,comprise a lead-in region, where it accepts the guide feature 403 evenif it is slightly misoriented. In the further course of the guide track,the guide feature 403 may be guided more tightly as compared to thelead-in region. The guide track may comprise an end stop 407, which isdesigned to abut the guide feature 403. The end stop may define an axialend position during the assembling process. In the region of the endstop 407, the guide track may comprise a curved surface, where thecurvature, preferably, matches the one of the guide feature. Thisfacilitates provision of a large area bearing surface between the twocap components in the end position.

The guide track 401 may extend in the axial direction over a lengthwhich is greater than or equal to one of the following values: 0.25*L,0.3*L, 0.35*L, 0.4*L, 0.5*L, 0.55*L. Alternatively or additionally, theguide track 401 may extend in the axial direction over a length which isless than or equal to one of the following values: 0.8*L, 0.7*L, 0.6*L.“L” is the length of the first cap component, the second cap componentor of the cap or cap assembly. The guide feature 403 may extend in theaxial direction over a length which is less than the axial extension ofthe guide track, particularly less than a quarter of the axial extensionof the guide track 401.

The guide feature 403 may protrude from a main body of the respectivecap component by 0.5 mm or more, preferably by 1 mm or more.

The guide feature may be arranged at a distance from the proximalopening of the cap or the second cap component. This distance ispreferably greater than the distance of the proximal end of the guidingfeature 172 a or 162 from the distal end of the first or second capcomponent, respectively.

In order to assemble the cap assembly, the first cap component 131 andthe second cap component 130 are arranged such that the guide feature403 and the guide track 401 are brought into a mechanical cooperation.Preferably, for doing so, at first the surfaces of the cap components inregions 405 and 404 interact to ensure pre-alignment of the guidefeature 403 and the guide track 401. This ensures preferably at leastthat the guide feature 403 can cooperate with the lead-in region of theguide track 401. Alternatively, a lead-in region might not be requiredif the pre-alignment is accurate enough to ensure that the guide feature403 always engages the guide tack 401. Once the lead-in region has beenpassed, the axial movement between the first and the second capcomponent is tightly guided axially by the axial guiding interface whichis then formed by the guide feature and the guide track such thatrelative rotation between the two cap components is prevented.Accordingly, it can be assured that the guiding feature 162 does guidethe connection feature 154 of the third cap component appropriately tothe corresponding fixing feature provided on an interior of the firstcap component 131, such that the features can interact to connect thefirst and third cap components. This ensures that the cap is reliablyassembled. Without this interface a significant relative rotation wouldstill be possible, such that the fixing features of the first and thirdcap components could not interact reliably as explained in theintroductory section. The tighter axial guiding via the guidinginterface ensures that the cap components do have a defined relativeposition. A situation which is just before the assembling process hasbeen finished is shown in FIG. 42 A on account of a partial sectionalview and in FIG. 42 B based on a side view. The second cap component hasalmost reached its end position with respect to the first cap component.In the end position, the guiding interface is preferably still active.Expediently, the guide feature 403 may interact with the end stop 407 inorder to indicate that the end position has been reached.

In FIG. 43 it is immediately apparent how the bump or pip 404 of theclip element rests in the depression 166, which simultaneously definesthe guide feature 403 in the interior. The curved surface(s) of theguide feature have the advantage that the guide feature can, on itscurved surface, take up some manufacturing tolerances, as along theradial extension of the curved surface there are different points wherethe guide feature could interact with a guide track.

It should be readily acknowledged that the guide track could also beprovided on the second cap component and the guide feature could beprovided on the first cap component. However, it is preferred that theguide track is provided on the first cap component and the guide featureon the second cap component, because by using the hemisphericaldepression as defining the hemispherical guide feature, the aestheticappearance of the cap is not negatively affected as it might be, if aridge were formed on the exterior surface to define a groove as guidetrack on the interior surface of the cap component.

The proposed design of the second cap component (which later forms theouter shell of the cap or cap assembly) enables the second cap componentto be made of metal or a metal based alloy on a single press designedfor deep drawing, without the requirement for any secondary formingoperations to be added to the component after deep drawing. Thisminimizes cost and maximizes the output from the process, enabling a lowcost drug delivery device to be assembled without sacrificing theaesthetic and perceived quality. Further, on account of the guidinginterface which is formed a defined angular orientation of the capcomponents can be ensured.

The scope of protection is not limited to the examples given hereinabove. The disclosed subject matter is embodied in each novelcharacteristic and each combination of characteristics, whichparticularly includes every combination of any features which are statedin the claims, even if this feature or this combination of features isnot explicitly stated in the claims or in the examples.

LIST OF REFERENCES CHARACTERS

1 drug delivery device

10 outer housing part

11 distal part

12 rotational hard stop/stop features/second rotational stop

13 aperture

20 inner body/housing

21 external thread

22 splines

23 bayonet features

24 window retention nose/retaining means

25 stop faces/first rotational stop

30 piston rod

31 bearing

32 external thread/first outer thread

33 external thread/second outer thread

40 driver

41 distal driver part/separate components/distal portion/first component

42 proximal driver part/separate components/proximal portion/secondcomponent

43 coupler

44 external thread/helical groove

45 stop faces

46 splines

47 teeth features

48 fingers/flexible arms

49 bearing surface

50 dose nut

51 stop faces

52 external ribs

53 internal thread

60 display member

61 number sleeve/first component

62 dial sleeve/other component

63 stop face

64 helical drive face/protruding thread

65 clutch features/teeth

66 bearing face/flange/contact features

67 opposite faces

68 ratchet arm/dispense clicker/clicker feature

70 button

71 ratchet teeth/dispense clicker/clicker teeth

72 end face

73 arms/fingers

74 snap features

80 cartridge holder

81 cartridge

82 bayonet connection

83 aperture

84 distal end

90 clutch

91 drive sleeve splines

92 clutch biasing teeth

93 snap apertures/snap features

94 splines

95 clutch teeth

100 clicker

101 distal clicker part/second toothed element

102 proximal clicker part/first toothed element

103 spring

104 splines

105, 106 clicker teeth

107 external splines

108 shaped splines

109 clutch biasing teeth

110 spring

120 cap

230 window

101 distal clicker part

102 proximal clicker part

130 outer part/metal element of cap/outer cap element

131 inner part/plastic element of cap/inner cap element

132 metal element of outer housing part

133 plastic element of outer housing part

134 fixing element/clip element

135 aperture of cap

136 aperture of outer housing part

137 end face (of cap)

141 proximal section

143 cavity

147 edge

149 cap snap means

151 deformable region

153 internal bump feature

155 cap retention feature

157 elevation

161 folded end

171 cavity

173 proximal end

150 guiding element

152 receiving portion

154 connection feature

156 feature

158 guiding portion

160 attachment feature

162 corresponding guiding feature

164 opening (outer part)

168 fixing portion

166 depression

170 corresponding connection feature

172 opening (inner part)

172 a guiding feature

180 cartridge/cartridge holder

182 injection needle

200 cap assembly

300 first component

301 second component

302 retaining feature

303 tip

304 cavity/clearance region

401 guide track

402 region

403 guide feature

404 region

405 region

406 distal end region

X longitudinal axis

The invention claimed is:
 1. A cap assembly for a drug delivery device,the cap assembly comprising: a first cap component; and a second capcomponent, wherein the first cap component is assembled to the secondcap component, wherein one of the first cap component and the second capcomponent is provided with a guide track and another one of the firstcap component and the second cap component is provided with a guidefeature, wherein the guide track and the guide feature are arranged tocooperate to form an axial guiding interface between the first capcomponent and the second cap component, wherein the axial guidinginterface is configured such that relative rotational movement betweenthe first cap component and the second cap component is restricted orprevented, wherein the guide track is provided on the first capcomponent and the guide feature is provided on the second cap component,wherein the guide feature is formed by a protrusion provided on an innersurface of the second cap component, and wherein an outer surface of thesecond cap component comprises a depression, where the protrusion isdefined by the depression.
 2. The cap assembly of claim 1, wherein thefirst cap component and the second cap component are configured suchthat, aside from the guiding interface, relative angular orientations ofthe first cap component and the second cap component, in which the firstcap component can be assembled to the second cap component are limitedto a range of orientation angles, and wherein the axial guidinginterface is configured to restrict the relative rotational movement toa restricted range of angles where the restricted range of angles is asubset of the range of orientation angles.
 3. The cap assembly of claim2, wherein the cap assembly comprises a third cap component that isfixed to the first cap component by means of a first cap componentfixing feature provided on the first cap component, which is designedand arranged to cooperate with a third cap component fixing featureprovided on the third cap component in order to fix the third capcomponent to the first cap component, wherein the second cap componentcomprises a fixing guide track that is arranged to guide movement of thethird cap component fixing feature to the first cap component fixingfeature, and wherein the third cap component fixing feature and thefirst cap component fixing feature are arranged to cooperate when theyare arranged in a fixing range of relative angular orientations, whereinthe fixing range does fully cover the relative angular orientations inthe restricted range of angles but does not fully cover the relativeangular orientations in the range of orientation angles.
 4. The capassembly of claim 1, wherein the cap assembly comprises a third capcomponent that is fixed to the first cap component by means of a firstcap component fixing feature provided on the first cap component, whichis designed and arranged to cooperate with a third cap component fixingfeature provided on the third cap component in order to fix the thirdcap component to the first cap component, and wherein the second capcomponent comprises a fixing guide track that is arranged to guidemovement of the third cap component fixing feature to the first capcomponent fixing feature.
 5. The cap assembly of claim 4, wherein thefixing guide track and the guide track extend in a common plane.
 6. Thecap assembly of claim 4, wherein the first cap component is asleeve-like component, the second cap component is another sleeve-likecomponent, and the third cap component is a clip element, and the secondcap component forms an outer surface of the cap assembly.
 7. The capassembly of claim 1, wherein the second cap component is made of a metalor of a metal alloy and is a deep drawn component.
 8. The cap assemblyof claim 1, wherein the cap assembly comprises a third cap componentthat is fixed to the first cap component by means of a first capcomponent fixing feature provided on the first cap component, which isdesigned and arranged to cooperate with a third cap component fixingfeature provided on the third cap component in order to fix the thirdcap component to the first cap component, wherein the second capcomponent comprises a fixing guide track that is arranged to guidemovement of the third cap component fixing feature to the first capcomponent fixing feature, and wherein a section of the third capcomponent is arranged in the depression.
 9. The cap assembly of claim 1,wherein the guide feature comprises one or more curved surfaces that aredesigned to interact with the guide track.
 10. The cap assembly of claim1, wherein the guide track is an axial guide track that extends in anthe axial direction.
 11. The cap assembly of claim 1, wherein the firstcap component and the second cap component are secured to each othersuch that relative rotational and axial movement is prevented.
 12. Thecap assembly of claim 1, wherein the cap assembly comprises a third capcomponent and a section of the third cap component is arranged in thedepression.
 13. A drug delivery device comprising: a cap assemblycomprising: a first cap component and a second cap component, whereinthe first cap component is assembled to the second cap component,wherein one of the first cap component and the second cap component isprovided with a guide track and another one of the first cap componentand the second cap component is provided with a guide feature, whereinthe guide track and the guide feature are arranged to cooperate to forman axial guiding interface between the first cap component and thesecond cap component, wherein the axial guiding interface is configuredsuch that relative rotational movement between the first cap componentand the second cap component is restricted or prevented, wherein theguide track is provided on the first cap component and the guide featureis provided on the second cap component, wherein the guide feature isformed by a protrusion provided on an inner surface of the second capcomponent, and wherein an outer surface of the second cap componentcomprises a depression, where the protrusion is defined by thedepression; and a cartridge containing a plurality of doses of a drug,wherein the drug delivery device is configured such that the cartridgeis replaceable.
 14. A kit for assembling a multi-part cap for a drugdelivery device, the kit comprising: a first cap component and a secondcap component, which can be assembled for a cap assembly, wherein thefirst cap component can be received in and secured relative to thesecond cap component, and wherein one of the first cap component and thesecond cap component is provided with a guide track and another one ofthe first cap component and the second cap component is provided with aguide feature, wherein the guide track and the guide feature arearranged to cooperate to form an axial guiding interface between thefirst cap component and the second cap component, wherein the axialguiding interface is configured such that relative rotational movementbetween the first cap component and the second cap component isrestricted or prevented, wherein the guide track is provided on thefirst cap component and the guide feature is provided on the second capcomponent, wherein the guide feature is formed by a protrusion providedon an inner surface of the second cap component, and wherein an outersurface of the second cap component comprises a depression, where theprotrusion is defined by the depression.
 15. A method for assembling amulti-part cap for a drug delivery device, the method comprising:providing a first cap component; providing a second cap component,wherein one of the first cap component and the second cap component isprovided with a guide track and another one of the first cap componentand the second cap component is provided with a guide feature, whereinthe guide track and the guide feature are arranged to cooperate to forman axial guiding interface between the first cap component and thesecond cap component, and wherein the axial guiding interface isconfigured such that relative rotational movement between the first capcomponent and the second cap component is restricted or prevented,wherein the guide track is provided on the first cap component and theguide feature is provided on the second cap component, and wherein theguide feature is formed by a protrusion provided on an inner surface ofthe second cap component, and wherein an outer surface of the second capcomponent comprises a depression, where the protrusion is defined by thedepression; introducing the first cap component into the second capcomponent such that the axial guiding interface is established, movingthe first cap component and the second cap component relative to oneanother in an axial direction towards an end position, this movementbeing guided by the axial guiding interface; and securing the first capcomponent and the second cap component to one another in the endposition.